"Hold Cmd-Q to Quit" from Chrome

This is a change - Chrome thinks this is correct default behavior and shipped this enabled.

• You can double press the Q - hold command and press and release Q twice as quickly as you are comfortable - ⌘ Q Q
• Or change the default to match your expectations and all other programs - see below to change the default setting

Select Chrome in the menu bar and select to un-check Warn before Quitting (⌘Q)

This can also be found in Chrome's Preferences (Cmd,), in the Appearance section:

Still happy with the answer given, but I did find out, by accident, that if you hold command and do a double tap on Q it quits instantly in spite of that option being selected.

Only found out as I have to quit chrome on computers in the lab often...